Alexander could see what David was trying to warn him about. But he was already aware of the massive drain fusing with the demons gave.
He guessed that anyone who found the ring in David's timeline probably insisted they were strong enough, and Solomon felt urgency enough from the outside situation that he didn't test them properly.
He could tell some demons in the ring didn't entirely respect him, even though he defeated them in combat. Or course, Solomon had leveled the playing field, with the demons never having more mana than him, he still defeated all of them.
He surmised from this that anyone that hadn't shown the demons what they were made of would have little to no respect from the more prideful of them. This could cause them to turn on the user of the legacy.
But it wasn't his case.
